936 DR."gWYN JEFFREYS ON THE MOLLUSCA OF THE [NoV. 29, 



^ 5. Thracia corbuloidea, de Blainville. 



T. corbuloidea, de Blainv. Diet. Sc. Nat. xvi. p. 514 ; Atlas, 

 pi. 76. f. 7. 



'Porcupine' Exp. 1870: Med. St. Cartagena B. (fragment). 



Distribution. S.W. France, Mediterranean and Adriatic. 



Fossil. Pliocene : lied 1 and Coralline Crag, Italy. Post-tertiary : 

 Calabria. 



Sijn, T. infiata, J. Sowerbj', T. subtilissima of Renier according 

 to Nardo, T. maraviffnce, Aradas and Calcara according to Aradas 

 and Tiberi. The young is T. meneghiniana of Aradas. The spe- 

 cific name is erroneously spelt corbuloides by modern authors. 



Family XX. Corbtjlid^. 



1. PoROMYA GRANULATA, Nyst & Westendorff. 



Corbula granulata, Nyst & West, Coq. Foss. d'Anvers, p. 6, pi. iii. 

 f. 3. 



P. granulata, B. C. iii. p. 4.5, pi. ii. f . 3 ; v. p. 191, pi. xlix. f. 1. 



'Lightning' Exp. St. 2. 



'Porcupine' Exp. 1869 : St. I, 23«. 1870 : Atl. 10, 24, C. Sa- 

 gres, 24, 26-30, 36 ; Med. Cartagena B., 50, Beuzert Road, Adven- 

 ture Bank, off Rinaldo's Chair. 



Bistribution. Loffoden Is. to the Mge&n and Adriatic, Madeira, 

 G. Mexico, off Barbadoes and Sombreros (' Blake ' Exp.), New Eng- 

 land and Maine ; 15-300 fms. 



Fossil. Pliocene : Coralline Crag, Antwerp Crag, S. France, 

 Calabria and Sicily. Not P. granulata of Philippi from the Miocene 

 formation of N.W. Germany. 



2. PoROMYA NE.EROiDES, Seguenza. (Plate LXX. fig. 8.) 

 P. nearoides, Seg. Boll. d. R. Com. geol. 1877, p. 270. 

 'Porcupine' Exp. 1870 : Atl. St. 23a, 24, 28o. Valves. 



. Bistribution. G.Mexico; J 14 fms. 



Fossil. Pliocene : Calabria and Sicily. 



P. tuberata, Jeffreys MS. The present species differs from 

 P. granulata in having greater breadth in proportion to the length, 

 in not being strongly angulated on the posterior side, and especially 

 in the sculpture, which consists of close-set longitudinal lines of 

 minute prickly tubercles instead of irregularly disposed granules. 



A. Smooth. Typical. 

 1. Ne^ra trxjncataS Jeffreys. (Plate LXX. fig. 9.) 



Shell squarish, very convex, moderately solid, opaque, glossy : 

 sculpture, smooth, with the exception of irregular but rather nume- 

 rous lines of growth ; rostrum short but broad, separated or defined 

 by a gradual indentation ; it has two slight ridges or keels extending 

 outwards from the beak at an acute angle : colour whitish : margins 



Lopped oflF, 



